1. Field of the Invention
The present invention relates to EMI (electromagnetic interference) shielding technology of using conformal shielding in package process to prevent EMI and more particularly, to a package structure with conformal shielding and inspection method using the same that is practical for conformal shielding application as well as compartment shielding application.
2. Description of the Related Art
The technique of conformal shielding is to form a conductive shielding layer on the periphery of an electronic module by means of sputtering, spray coating or any other film coating technique. Prior to the film coating step, the fabrication of the electronic module employs a substrate cutting step. After the substrate cutting step, many inner grounding structures are exposed to the outside of the substrate. After covered on the module, the conductive shielding layer is electrically connected with the inner grounding structures to protect the circuits of the module against external electromagnetic noises.
However, a substrate cutting failure, uneven thickness of the conductive shielding layer or improper connection between the conductive shielding layer and the inner grounding structures may lead to poor shielding performance. To ensure the quality of conformal shielding, shielding performance inspection of every fabricated package structure must be inspected by means of X-ray scanning or destructive cross-sectional inspection. As a result, it needs to use an expensive X-ray scanner, or to destruct the finished product, increasing the amount of waste material. An improvement in this regard is necessary.